1. Field of the Invention
The invention relates to filter vessels used to filter gas and liquid streams such as natural gas and natural gas processing liquid streams and to filter elements for such vessels, and, more specifically, to an improved structure and method for mounting the filter elements within the interior of the associated filter vessel.
2. Description of Related Art
Gas filter elements for filtering dry gas streams as well as for separating solids and liquids from contaminated gas streams are well known, as are gas filter elements for coalescing entrained liquids from a gas stream. Often these types of gas filter elements are installed in multi-stage vessels, which are in turn installed in a gas pipeline, to perform these filtering functions. U.S. Pat. No.'s 5,919,284, issued Jul. 6, 1999, and U.S. Pat. No. 6,168,647, issued Jan. 2, 2001, both to Perry, Jr., and assigned to the assignee of the present invention, disclose multi-stage vessels using individual separator/coalescer filter elements to separate solids, filter liquids, and coalesce liquids. The foregoing multi-stage vessels, as well as a multitude of other similar filtration vessels used in industry utilize solid or hollow core tubular elements, typically formed at least party of a porous filtration media. For example, porous filtration elements useful in the above type of filtration vessels are of the same general type as those that are described in U.S. Pat. No. 5,827,430, issued Oct. 27, 1998 to Perry, Jr., et al., and assigned to the assignee of the present invention.
It is periodically necessary to perform maintenance on the filtration vessels, including replacement of the porous filter elements. This task has been labor intensive and time consuming in the past because of the mounting structure used to mount the filter elements within the filtration vessel interior. Often, it was necessary to unscrew and end cap or nut to free the filter element from its associated structural mounting within the vessel interior. Not only was this time consuming, but the location of the mounting structure was sometimes inconvenient to access, making filter replacement a difficult or inconvenient chore. The same type of inconveniences were present in the initial filter installation process for new filtration vessels.
Thus, despite various advances which have been made in overall filtration vessel design, there continues to be a need for improvements which simplify the process of mounting and replacing filter elements within the filtration vessel, thereby decreasing the cost of vessel installation and maintenance.